Lock



C. J. DIALS 4 Jan. 5, 1937.

LOCK

Filed Oct. l, 1935 3 8 4M /3 4 5 j l 7 M 9U 6 .0 Jl. u 91 M F 6 3 7 R 44 'Il \5 Il? Cray'ton/ J. Dzlals 'BY .m

ATTORNEY Patented Jan. 5, 1937 UNITED STATES PATENT OFFICE 9 Claims.

This invention relates to locks, and particularly to those of thepadlock type.

The main objects of my invention are to provide a lock in which airpressure instead of the usual mechanical connections retracts thelockbolts; and which is so constructed that the lock is pick and tamperproof, and can positively only be opened by the use of a proper key.

A further object of the invention is to produce a simple and inexpensivedevice and yet one which will be exceedingly effective for the purposefor which it is designed.

These objects Iy accomplished by means of such structure and relativearrangement of p-arts as will fully appear by a perusal of the followingspecification and claims.

In the drawing similar characters of reference indicate correspondingparts in the several views:

Figure 1 is a sectional yelevation of my improved lock, with theshacklein locked position and the key removed.

Figure 2 is a similar view, showing the key in place and with the boltsretracted and the shank being retracted.

Figure 3 is a bottom plan View of the lock.

Referring now more particularly to the characters of reference on thedrawing, the numeral I denotes the body or housing of the lock, whichmay be a one-piece mem-ber and preferably of oblong form as shown inFigure 3.

Formed in the body adjacent its opposite sides are cylindrical bores 2,extending in parallel relation from the top of the body to a point nearthe bottom thereof. The upper portions of these bores form guides forthe lower ends of the U shaped shackle 3 of the lock, while the lowerportions form pump cylinders in which plungers 4 of any suitablematerial are snugly and slidably disposed. Compression springs 5 in thecylinders between the bottom thereof and the plungers act to force thelatter upward; the springs becoming slack before the plungers reach thetop of the bores, so that they canno-t be displaced from position by thesprings.

Formed in the body near the top and extending toward each other from andradial'with the adjacent sides of the bores :2 are smaller cylinders 6,in which lock bolts l are snugly slidable. The outer ends of the boltsare preferably tapered, and are adapted to engage notches 8 cut in theadjacent faces of the legs of the shackle. Springs 9 in the cylinders 6behind the bolts, urge the latter outwardly and into the notches andwhen the bolts are thus engaged, the springs 5 hold the plungers Ilagainst the lower ends of the shackle legs, thus preventing rattling andholding the shackle snugly in a locked position.

Formed in the body centrally between the bores 2 and projecting upwardlyfrom the bottom of the body is a key socket I 0. Ilhis is preferably ofnon-circular tapering form. Air passages II lead from the cylinders 6 attheir inner ends to the socket il) near the top and on opposite sides.Other air passages i2 lead from the bottom of the cylinders 2 to thesocket I Il near the bottom. Release air passages I3 lead from thesocket II) intermediate its ends to the bores 2 above the bolts, orwhere such passages communicate with the air pockets form-ed in thebores by the notches B when the shackle is in place. The various airpassages are holes drilled through from the outside of the body, theunwanted portions of the drill holes being then plugged up as iscommonly done. The cylinders 6 are of course formed in the same way.

A special key I4 is provided for use with the lock, having a stem I5 ofthe same shape `and taper as the socket II), so as to non-turnablyfandsnugly fit in the same. The stem I5 has passage means I6 drilled thereinto establish unbroken.

communication between the passages Il and I2, when the key stem isproperly inserted, vbut shutting oi the socket ends of the releasepassages I3.

In operation, the shackle 3 may, of course, be

mounted on the body by merely depressing the ends of the shackle intothe bores 2 until the bolts engage the notches 8, the bolts retractingas they engage the unnotched portion of the shackle, as

usual.

The provision of the release passages I3 enables might otherwise beconfined by the initial depression of the shackle, to be forced out andinto the key socket. f

Also, it will` be .noted that one of the Apassages .I3 terminates atsocket I0 between the #termination of passages I I. This preventsthelock from being opened by a tapered thimble which might be placed inthe socket instead of a key to cover both passages I3 while leaving bothpassages Il open, and then applying a suction to theend of the' socketto retract the bolts-something which could be done if both,passages I3`were below passages ,I I, but which cannot bedone ywith the arrangementshown, as will be evident.

To open the lock, the shackle is depressed beyond a locking position, oras indicated in dotted lines in Figure 2, and before the key isinserted. 'Ihis lowers the plungers 4 against the resistance of springs5, expelling the Aair ,from the cylinders air in the upper vportion ofthe bores, and which through passages l2 which are now open toatmosphereat socket I0. The key is then inserted, and the shackle is released. Thesprings 5 then act to lift the plungers, and since the passages l2 areno longer in communication with atmosphere but with the cylinders 6through passages Il and key passages I6, a tendency to vacuum is set upin cylinders 6. Since the outer ends of bolts 'l are exposed toatmosphere through notches 8 and the narrow passageways formed betweenthe 4bores 2 and the loosely fitting shackle, the relatively great airpressure on the outer ends of the bolts will force the same inwardly andclear, of the notches 8. The shackle may then be withdrawn, as shown. l

When the key is withdrawn, the vacuum tendency is of course broken andthe springs 9 immediately force the bolts out. Since the lock bolts andtheir holding springs are offset and in compartments separate from thesocket, they cannot be reachedkand' picked by any tool inserted in thesocket/and the use of the proper key, together with thenecessary airpressure, :are

. still in practice such deviations from such detail may be resorted toas defined by the appended claims.

Having thus kdescribed my invention, what I claim as new and useful anddesire'to secure by `Letters Patent is:

1. A lock comprising a body having a blind bore,

`a shackle slidably and releasably mounted in the bore, a cylinder'inthe body radially of and extending to the bore near its outer end, alock boltslidable in the cylinder, the shackle having a notch in` itsside with which the outer end of the bolt is' engageable and havingmeans to allow of depressing movement of the shackle beyond a boltengaging position, a plunger in the bore below and engageable with theend of the shackle, a spring yieldably holding the plunger againsttheshackle, the body having a key socket openat its I`outer end toatmosphere, an air passage from` the bottom of the body bore to saidsocket, another air passage from the socket to the bottom of the bolt fcylinder; said passages being adapted to cooperate with a key steminsertable with a close flt into said socket, the key stem having an airpassage vto'establish direct communication between the socket ends ofthe first named air passages.

2.` A lock Ycomprising a body, a shackle having .la le'g slidably andremovably mounted in the body and having a notch in one side disposedin- 'side the .body when the shackle is in position, a

lock bolt to releasably engage said notch, a cylinder vin the body Yinwhich said bolt is slidably mounted, another cylinder in the body, thelatter having a key socket, separate air passages from the cylinders toterminations at the walls of said socket, saidpassages being adapted tocooperate' with a key stem to closely t in said socket, said stem havingan air passage to then establish directcommunication between the socketends of body.

said rst named passages, and means operable by the depression of theshackle beyond a locking position and its subsequent releasefrom suchdepression Vfor setting up a tendency to vacuum l in the communicatingair passages.

3. A lock comprising a body, a locking bolt mounted therein for movementfrom a locking to a release position, a cylinder in which the bolt isslidable, said bolt at its outer end being exposed to atmosphere, andmanually operable means mounted in the body to set up a negativepressure in the cylinder to cause the bolt to be withdrawn to a releaseposition by atmospheric air pressure on the exposed end of the bolt.

4. A lock comprising a body, a locking bolt mounted therein for movementfrom a locking to a release position, a cylinder in which the bolt isslidable, said bolt at its outer end being exposed to atmosphere, anormally broken air passage extending in the body from the cylinderbehind the bolt, said passage being adapted to cooperate with aremovable key having a passage to close the break and complete said airpassage, and manually operable means mounted in the body and' to whichthe passage is connected beyond the break to set up a negative pressurein the passage only when the key is in place.

5. A structure as in claim 4, in which said last named means comprises acylinder to which the end of the air passage furthest from the boltcylinder is connected, a manually depressible plunger in the cylinder,and a spring to move the plunger in opposition to its depressingmovement and away from the passage.

6. A` lock comprising a body, a locking bolt mounted therein formovement from alocking to a release position, means mounting the boltfor lmovement to a release position by air pressure,

and manually and rselectively operable means' mounted in the body toenable such air pressure to function upon the insertion of a key in the7. A lock comprising a body, a shackle releasably mounted on the body, alocking bolt in the body to releasably engage the shackle and thenholding the same againstrelease, means mountingthe bolt for movement toa release position byi air pressure, and means to enable such airpressure to function and including a pump plunger actuated by movementof the shackle in one direction;

8. A lock comprising a body, a shackle releasably mounted on the body, alocking bolt in the body to releasably engage the shackle and thenholdingthe same against release, means mounting the bolt for movement toa release position by air pressure, `and means to enable such airpressure to function and including a pump plung er actuated by movementof the shackle in a direction opposite to that necessary to release the'shackle from the body.

9. A structure asin claim 2, there being an additional passage fromatmosphere to the socket and communicating therewith at a point betweenthe outer end of said socket and the point of termination of thekey-cylinder passage in said socket, said additional passage beingclosed 'by the key stem when the latter is inserted.

CRAYTON J. DIALS.

